Mo,
Do what you can, when you can.
But-
The idea in firing several groups at a session is to allow you to settle in and concentrate on all aspects.
I don't know about others, but I do T&E sessions that involve hours at a time, with anywhere from 100 to 300 rounds through an individual gun.
I frequently find it can take me 20 or thirty shots in some cases, depending on the gun, just to settle in & warm up.
I'm not sure you understand quite what's involved in where you're trying to go.
An occasional episode where you only shoot one or two targets is not going to get you to a point where you can expect to realistically enter competition anywhere, with any gun, if that's what you'd like to do someday, as you've mentioned.
I don't mean, as I've said before, to criticize your Dad, but you need to understand that it'll take regular practice with your gun to really progress, and that's as a foundation for moving back up to the milsurps eventually, too.
30-minute firing sessions is sorta a minimum.
Allows you to take a leisurely pace, concentrate, check targets, note results, take a short break in between, keep it relaxed, and still fire enough rounds to analyze & build muscle memory & repetitive patterns.
You need to understand that yourself, and to communicate that with your father.
It'll take time, and it'll take dedicated practice.
A casual pop-off-a-few-all-jumbled-up-on-one-target approach won't do much for you, if you want to get very far.
Don't push for today if it's too hot there.
But, we'll need enough groups on enough targets to determine a trend, and one or two won't do that very well.
The more data, the better the end analysis.
If you can't shoot 5 targets in a single outing, you're really handicapped.
No disrespect to either of you, but you both need to understand that.
Denis